This application claims the priority of German application 201 02 451.9, filed Feb. 13, 2001, the disclosure of which is expressly incorporated by reference herein.
The present invention relates to a wheel bearing unit for a motor vehicle comprising a wheel bearing arranged in a pivot bearing, and a received propeller shaft which, by way of a joint bell, is situated opposite a receiving element of the pivot bearing.
In a wheel bearing unit according to German Patent Document DE 44 25 732 A1, a sealing element is provided between a wheel bearing and a joint bell for sealing off a ring gap. On one side, this sealing element is supported on the bearing and, on the other side, the sealing element is supported on the joint bell.
It is an object of the invention to provide a light weight wheel bearing unit, such as a wheel carrier/pivot bearing and a propeller shaft with a joint bell for a motor vehicle, which ensures optimal sealing between the joint bell and the wheel bearing unit or a drive shaft.
According to the invention, this object is achieved by way of directly opposite areas of the receiving element and of the joint bell having reductions of their thicknesses, and a sealing ring, which can be pressed upon the propeller shaft, by which a forming ring gap between the receiving element and the joint bell can be bridged. Additional advantageous characteristics are reflected in various claims.
A process of ensuring optional sealing in a wheel bearing unit is also claimed.
Principal advantages achieved by the invention include enlarging a conventionally narrow ring gap between a joint bell and a receiving element of a pivot bearing for weight reduction. This takes place by way of the reduction in thickness of the directly opposite areas of the receiving element and of the joint bell, and by bridging the forming ring gap by way of a sealing ring, which can be pressed onto the propeller shaft, or an additional component.
According to the invention, the reduction of weight at the joint bell and at the wheel carrier/pivot bearing can advantageously be achieved, but the ring gap between these two components is enlarged, resulting in the risk of contamination. In order to counteract this, the relatively large ring gap is covered by a sealing ring which has a low weight. On the whole, therefore, the weight of the wheel bearing unit is reduced.
The sealing element or the sealing ring can rotate along on the propeller shaft, be mounted on the propeller shaft, or be arranged on the pivot bearing/wheel carrier without rotating along with the carrier.
Weight reduction is achieved by reducing the thickness of the pivot bearing at the receiving element as well as at the joint bell as a result of removal of material. This reduction of thickness is advantageously taken into account already during the manufacturing of the parts. As a result of the construction and positioning of the joint bell with respect to the pivot bearing, the ring gap achieved cannot be reduced, so that a sealing ring is required. This sealing ring is held by one leg on the propeller shaft, and another leg, at the end of the sealing ring which faces away, rests tightly against the joint bell. The intermediate area of the sealing ring is correspondingly bent and rests by way of a projecting edge against the receiving element of the pivot bearing. This sealing ring may also have a different shape.
Removal of material on the joint bell preferably extends along a circle segment from an attachment or a shackle toggle joint to approximately the jointing plane of the bearing. As a result, material removal can take place over a relatively large area without impairing the stability of the joint bell. Correspondingly, removal of material on the receiving element of the pivot bearing which, on the end side of the receiving element, consists of an enlargement of the inside diameter, is provided. This removal of material also ensures a robust tight fit of the bearing.